Cosmic Rays for ATLAS Cosmic Rays for ATLAS Commissioning Commissioning Commissioning MeetingCommissioning Meeting
ATLAS Physics WorkshopATLAS Physics Workshop
Athens May 2003Athens May 2003
Halo+Cosmics group:Halo+Cosmics group: M.Boonekamp, F.Gianotti, M.Boonekamp, F.Gianotti, R.McPherson, P.Nevski, J.Pinfold, R.SolukR.McPherson, P.Nevski, J.Pinfold, R.Soluk
Cosmics Info:Cosmics Info: http://cern.ch/rmcphers/atlas/cosmics/ http://cern.ch/rmcphers/atlas/cosmics/
Athens May 2003 ATLAS Physics Workshop 2
OverviewOverview
Scheduled ~ 40 days of cosmic running end 2006Scheduled ~ 40 days of cosmic running end 2006 Could also imagine cosmic running with only Could also imagine cosmic running with only
calorimeters earlier, and further running in calorimeters earlier, and further running in January—March 2007 (machine cool down)January—March 2007 (machine cool down)
IS IT USEFUL? Study:Study:
Cosmic rates entering ATLAS cavern Hit or Geant “Digit” rate in different detector elements Calorimeter energy deposition (Triggers) (Offline Reconstruction)
Athens May 2003 ATLAS Physics Workshop 3
ATLAS GeometryATLAS Geometry
SX1
PX14PX16
PX15
UX15
USA15
Shafts (PX14 Shafts (PX14 and PX16) and PX16) Large windowsLarge windows
Critical to include in simulation
G3 GeometryG3 Geometry Surface buildings PX14, PX16 Shielding Concrete …
Athens May 2003 ATLAS Physics Workshop 4
Current Geant 3 simulationCurrent Geant 3 simulation
Rock ~ Silicon
600m x 600m x 200m deep
(2.33 g/cm3)
AirConcrete
Density = 2.5 g/cm3
Surface building
PX14/16 shielding
PX14
(14 m Inner Dia.)
PX16
(10 m Inner Dia.)
Full ATLAS Geant 3 Simulation (atlsim)
- Release 6.0.3
- Initial detector
- Full B fields
Athens May 2003 ATLAS Physics Workshop 5
In progress: refined descriptionIn progress: refined description
Ground density Ground density variation with depthvariation with depth
Suspension hallsSuspension halls Other caverns Other caverns
(USA15, US15)(USA15, US15) Being implemented by
R.Soluk and J.Pinfold in consultation with CERN civil engineers
Can be used for later simulations
Athens May 2003 ATLAS Physics Workshop 6
Cosmic Cosmic Flux Flux Two generators used so farTwo generators used so far
PDG approximation formula Single muon flux (Energy, cos ) Neglects muon decay-in-flight
Fit to measured fluxes Code from Alois Putzer (ALEPH simulation) Agrees at few % level with measured fluxes
Allkofer et al, Phys. Lett. 36B (1971), 425; A. Dar, Phys. Rev. Lett. 51 (1983), 227
For E > 50 GeV Agreement < 20% level between 2 generators
Third generator also under study (Soluk)Third generator also under study (Soluk) “CORSIKA” full cosmic ray shower program Useful for cosmic ray physics studies with ATLAS Includes “multi-muon” events, not present in other
generators
Athens May 2003 ATLAS Physics Workshop 7
Sample studiedSample studied
PDG single PDG single flux with cuts: flux with cuts: SURFACE :
0.35 < cos < 1 (above 70o hit earth’s
curvature)50 GeV < E < 5000 GeV -300 m < X0 < +300m -300 m < Z0 < +300m
(allow at 70o to enter ATLAS cavern)
ATLAS Y=0: use speed-up cuts (track extrapolation)
-30 m < X(Y=0) < +30 m -30 m < Z(Y=0) < +30 m
SURFACE RATES (before Y=0 cuts):
3 x 10-4 / (cm2 s)
1 x 106 / s
CURRENT SAMPLE:
1.2 x 109 18 min)
Athens May 2003 ATLAS Physics Workshop 8
Cosmics Cosmics in 0.01 sec in 0.01 sec
Athens May 2003 ATLAS Physics Workshop 9
Kine Distributions … Kine Distributions …
““Cavern”:Cavern”: ATLAS G3
volume
E, cos E, cos of of entering entering caverncavern
Athens May 2003 ATLAS Physics Workshop 10
Kine Distributions … Kine Distributions …
““Digit”:Digit”: Any G3 digit
(mostly MDT)
Athens May 2003 ATLAS Physics Workshop 11
Kine Distributions … Kine Distributions …
Through-goingThrough-going RPC digit, Y>0 RPC digit, Y<0 ID Digits
Can(?) adjust Can(?) adjust LVL1 RPC LVL1 RPC trigger for thesetrigger for these
Athens May 2003 ATLAS Physics Workshop 12
Kine Distributions … Kine Distributions …
Through-goingThrough-going RPC digit, Y>0 RPC digit, Y<0 Pixel Digits
LVL1 RPC trigger LVL1 RPC trigger should work (with should work (with timing adjustments)timing adjustments)
Athens May 2003 ATLAS Physics Workshop 13
Digit Distributions … Digit Distributions …
Detector planesDetector planes From digit
counting Number of
“ihit=1” hits
Athens May 2003 ATLAS Physics Workshop 14
Digit Distributions … Digit Distributions …
Detector planesDetector planes From digit
counting Number of
“ihit=1” hits
Athens May 2003 ATLAS Physics Workshop 15
Digit Distributions … Digit Distributions …
Detector planesDetector planes From digit
counting Number of
“ihit=1” hits
Athens May 2003 ATLAS Physics Workshop 16
Digit Distributions … Digit Distributions …
Detector planesDetector planes From digit
counting Number of
“ihit=1” hits
Athens May 2003 ATLAS Physics Workshop 17
Digit closest to (0,0,0) Digit closest to (0,0,0)
Athens May 2003 ATLAS Physics Workshop 18
EM Cal Transverse EnergiesEM Cal Transverse Energies
EM endcaps EM endcaps and barreland barrel
ECALREC for ECALREC for reconstruction reconstruction and clusteringand clustering
EM ScaleEM Scale
Athens May 2003 ATLAS Physics Workshop 19
Tile EnergyTile Energy
Tile calorimeterTile calorimeter Used DIGI(4) for Used DIGI(4) for
energyenergy EM ScaleEM Scale
Athens May 2003 ATLAS Physics Workshop 20
HEC EnergyHEC Energy
Hadronic ECHadronic EC Used DIGI(4) for Used DIGI(4) for
energyenergy EM ScaleEM Scale
Athens May 2003 ATLAS Physics Workshop 21
FCAL EnergyFCAL Energy
Forward CalForward Cal Used DIGI(4) for Used DIGI(4) for
energyenergy EM ScaleEM Scale
Athens May 2003 ATLAS Physics Workshop 22
Rates SummaryRates SummarySystemSystem ConditionCondition Rate (Hz)Rate (Hz)
ATLAS CavernATLAS Cavern ---- 34003400
Any G3 DigitAny G3 Digit ---- 14501450
ThroughThrough RPCRPCY>0Y>0 x RPC x RPCY<0 Y<0 x IDx IDDIGIDIGI 13.713.7
GoingGoing RPCRPCY>0Y>0 x RPC x RPCY<0 Y<0 x PIXx PIXDIGIDIGI 0.340.34
PassedPassed |Z|ZDIGIDIGI| < 300, |R| < 300, |RDIGIDIGI| < 60 cm| < 60 cm 6.056.05
originorigin |Z|ZDIGIDIGI| < 100, |R| < 100, |RDIGIDIGI| < 30 cm| < 30 cm 1.121.12
|Z|ZDIGIDIGI| < 60, |R| < 60, |RDIGIDIGI| < 20cm| < 20cm 0.320.32
EETTCELL CELL > 5 GeV> 5 GeV 0.090.09
EM CalEM Cal EETTCLUSTER CLUSTER > 5 GeV> 5 GeV 0.210.21
EETOTAL TOTAL > 5 GeV> 5 GeV 0.360.36
Tile CalTile Cal EETOTAL TOTAL > 20 GeV> 20 GeV 1.371.37
HECHEC EETOTAL TOTAL > 20 GeV> 20 GeV 0.140.14
FCALFCAL EETOTAL TOTAL > 20 GeV> 20 GeV 0.0150.015Rate error (generator comparisons) 20%
Athens May 2003 ATLAS Physics Workshop 23
Summary, Plans Summary, Plans Working cosmic Working cosmic G3 (atlsim) MC for ATLASG3 (atlsim) MC for ATLAS
Different generators 4-vectors samples of muons entering cavern ZEBRA event files for offline studies
Rates seem to be large enough for initial Rates seem to be large enough for initial electronics shake-downelectronics shake-down
Dead channel maps, electronics+DAQ checks, etc.
To-do: triggers and offline reconstruction …To-do: triggers and offline reconstruction … Simplified trigger studies: have input already for LVL1 RPC
(Gianpaolo Carlino, Leandro Nisati, Stefano Veneziano) and Tiles (Alan Watson), and also from Nick Ellis
Full trigger studies: switch to full ATHENA trigger simulations, currently under development
Many issues for both triggers and reconstruction due to non-pointing, out of time tracks must be studied
Studies: reconstruction, alignment, calorimeter calibration …